Tasmanian Catholic Education Office director Trish Hindmarsh said yesterday it was the first time such an amendment had been sought in Tasmania and was expected to go before Parliament when it resumed next week.

``We've been working with Anti-Discrimination Commissioner Robin Banks to have an amendment to the act to ensure priority places for Catholic families over other families when there is a contest for a place,'' Dr Hindmarsh said.

``We greatly value inclusivity, but if there's a contest for a place and where there might be only one place, we need to favour the Catholic family because Catholic schools intrinsically support Catholic families in the education of their child.''

Dr Hindmarsh said such an amendment already existed in other states' anti-discrimination acts, and was used particularly in cities like Sydney and Melbourne where there were large numbers of students trying to get into Catholic schools.

She said in most cases, Tasmanian Catholic schools could accommodate all those who applied but situations did arise where there were too few places.

The amendment was most likely to come into play for those starting school and those going in to high school.

Dr Hindmarsh said the Catholic system already had exemptions on religious grounds around the employment of teachers.

Tasmanian Catholic School Parents and Friends Federation president Damian von Samorzewski said he didn't believe there would be many instances when the amendment would have to be used.

He said the only complaint he'd ever heard about non-Catholics attending Catholic schools was from a parent about the dilution of the faith in one school.

But generally speaking, he believed the ratio of non-Catholic to Catholic students had changed considerably over the past 40 years.